As per RFC2368 which defines mailto:, further reinforced by an example in RFC1738, it is explicitly stated that the only valid way to generate a line break is with %0D%0A. See: stackoverflow Then, this behavior is not compliant and it seems to be a bug. There should be a white-list of allowed "rich text" like such as %0D%0A

Hahaaha a clear paradox 😅

Yes good idea. What was the title and text of your ticket so we can post something similar ?

Great. I’ll copy paste tomorrow ;-)

Done ;-)